1. Technical Field
Various embodiments relate to a wireless electronic device, and more particularly, to a portable electronic device, a wireless charging device for the same, and a wireless charging system.
2. Related Art
Portable electronic devices may provide various services such as voice communication service, text transmission and reception service, multimedia service, communication service, and electronic document service, without having time and space restraints.
The functions of the portable electronic devices have developed day by day. Recently, a variety of smart phones and smart pads, referred to as smart devices, have spread.
With the increase in number of services which can be used through portable electronic devices, users are enjoying a more convenient life. However, the number and complexity of operations to be processed by the portable electronic devices have significantly increased. Thus, the battery consumption of the portable electronic devices is inevitably increased.
In general, a portable electronic device is charged in a wired manner. That is, the portable electronic device and a power supply terminal may be coupled through a cable to charge the portable electronic device. In this case, however, a user must carry a charging cable, and cannot charge the portable electronic device when the user has no charging cable or power supply terminal to connect the charging cable at a necessary time.
Recently, a technique for charging a portable electronic device in a wireless manner has been developed.
Representative examples of the wireless charging method may include a magnetic induction method, a magnetic resonance method, an electromagnetic wave method and the like. The magnetic induction method transmits a current induced in a primary coil of a wireless charging device to a secondary coil of a portable electronic device, and provides a distance range of 0.5 to 1 cm. The magnetic resonance method has an advantage in that it provides a long distance range of 2 to 3 m, but requires an impact assessment for the human body because it uses electromagnetic waves of several MHz. The electromagnetic wave method provides a distance range of several tens km, but also requires an impact assessment for the human body.
Currently, wireless charging devices based on the magnetic induction method are manufactured to satisfy the WPC (Wireless Power Consortium) or PMA (Power Matters Alliance) standard.
The wireless charging system based on the magnetic induction method uses the principle that, when a portable electronic device is placed close to a charging pad of the wireless charging device including a primary coil to generate an electromagnetic field, a power receiver (secondary coil) of the portable electronic device receives magnetic energy according to electromagnetic induction, and charges a battery of the portable electronic device.
Thus, the charging pad must be manufactured in a flat type such that the portable electronic device is maintained within a distance of 0.5 to 1 cm from the charging pad of the wireless charging device, or may require an additional device through which the portable electronic device is attached to/from the wireless charging device. In particular, when the portable electronic device needs to be charged while moved on a vehicle in operation, a reliable fixing and separating device may be required to prevent the portable electronic device from coming off.